If you have windows 8 or newer, there should be a xfinity stream app, or you can just like the reviewer before said go to website, plug in your comcast username and password and your on way to watching movies and tv in seconds.
go to comcast.com on the right top corner you will see a tv icon. Hit the tv icon it will take you to sign in. You will need your username and password used to log in to pay your bill Nd boom you are logged in to your aaccput to watch tv!
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